Detecting Molecules of Biological Interest via Solid State Nanopores

Recently, interest in nanopore systems has grown due to their sensing abilities. They have the potential for uses in medical diagnosis and personalized medicine.

Solid-state nanopores are fabricated by drilling through a thin insulating membrane composed of Si₃N₄ using HR-TEM. The membrane is then placed between two chambers filled with an electrolytic solution and ionic current flowing through the pore is electrically monitored. Analytes can be driven through the pore by voltage application. When an analyte is translocated through the pore, a blockage in the ionic current, which is typical to the analyte, is observed.

We focus on improving the performance of solid-state nanopores in detecting analytes such as DNA, nanoparticles, and proteins. One approach is to use surface modifications, in order to improve surface properties of the Si₃N₄ membrane. We are covering the surface with dipeptide layer based on DOPA. This molecule can help improve the hydrophilicity of the Si₃N₄ pore and make it more efficient in measuring DNA molecules and attracting nanoparticle hybrids for the biomarker detection.

A nanopore is drilled in a Si3N4 membrane with high-resolution TEM. The membrane is placed in a flow cell, and ionic current is measured through the pore. An analyte is driven by voltage application. Current blocked when an analyte is translocated through the pore.